Plastic scintillator detectors are widely used in particle physics thanks to the very good particle identification, tracking capabilities and time resolution. However, new experimental challenges and the need for enhanced performance require the construction of detector geometries that are complicated using the current production techniques. In this article we propose a new production technique based on additive manufacturing that aims to 3D print polystyrene-based scintillator. The production process and the results of the scintillation light output measurement of the 3D-printed scintillator are reported.
The next generation of very-short-baseline reactor experiments will require compact detectors operating at surface level and close to a nuclear reactor. This paper presents a new detector concept based on a composite solid scintillator technology. The detector target uses cubes of polyvinyltoluene interleaved with $^6$LiF:ZnS(Ag) phosphor screens to detect the products of the inverse beta decay reaction. A multi-tonne detector system built from these individual cells can provide precise localisation of scintillation signals, making efficient use of the detector volume. Monte Carlo simulations indicate that a neutron capture efficiency of over 70% is achievable with a sufficient number of $^6$LiF:ZnS(Ag) screens per cube and that an appropriate segmentation enables a measurement of the positron energy which is not limited by gamma-ray leakage. First measurements of a single cell indicate that a very good neutron-gamma discrimination and high neutron detection efficiency can be obtained with adequate triggering techniques. The light yield from positron signals has been measured, showing that an energy resolution of 14%/$sqrt{E({mathrm{MeV}})}$ is achievable with high uniformity. A preliminary neutrino signal analysis has been developed, using selection criteria for pulse shape, energy, time structure and energy spatial distribution and showing that an antineutrino efficiency of 40% can be achieved. It also shows that the fine segmentation of the detector can be used to significantly decrease both correlated and accidental backgrounds.
Liquid-scintillator-based detectors are a robust technology that scales well to large volumes. For this reason, they are attractive for experiments searching for neutrinoless double-beta decay. A combination of improved photo-detection technology and novel liquid scintillators may allow for the extraction of particle direction in addition to the total energy of the particle. Such an advance would find applications beyond searches for neutrinoless double-beta decay.
This paper presents studies of the performance of water-based liquid scintillator in both 1-kt and 50-kt detectors. Performance is evaluated in comparison to both pure water Cherenkov detectors and a nominal model for pure scintillator detectors. Performance metrics include energy, vertex, and angular resolution, along with a metric for ability to separate the Cherenkov from the scintillation signal, as being representative of various particle identification capabilities that depend on the Cherenkov / scintillation ratio. We also modify the time profile of scintillation light to study the same performance metrics as a function of rise and decay time. We go on to interpret these results in terms of their impact on certain physics goals, such as solar neutrinos and the search for Majorana neutrinos. This work supports and validates previous results, and the assumptions made therein, by using a more complete detector model and full reconstruction. We confirm that a high-coverage, 50-kt detector would be capable of better than 10 (1)% precision on the CNO neutrino flux with a WbLS (pure LS) target in 5 years of data taking. A 1-kt LS detector, with a conservative 50% fiducial volume of 500~t, can achieve a better than 5% detection. Using the liquid scintillator model, we find a sensitivity into the normal hierarchy region for Majorana neutrinos, with half life sensitivity of $T^{0 ubetabeta}_{1/2} > 1.4 times 10^{28}$ years at 90% CL for 10 years of data taking with a Te-loaded target.
For the production of a polarized antiproton beam various methods have been suggested including the possibility that antiprotons may be produced polarized which will be checked experimentally. The polarization of antiprotons produced under typical conditions for antiproton beam preparation will be measured at the CERN/PS. If the production process creates some polarization a polarized antiproton beam could be prepared by a rather simple modification of the antiproton beam facility. The detection setup and the expected experimental conditions are described.
The performance of a novel tracking detector developed for the focal plane of the NSCL/FRIB S800 magnetic spectrometer is presented. The detector comprises a large-area drift chamber equipped with a hybrid Micro-Pattern Gaseous Detector (MPGD)-based readout. The latter consists of a position-sensitive Micromegas detector preceded by a two-layer M-THGEM multiplier as a pre-amplification stage. The signals from the Micromegas readout are processed by a data acquisition system based on the General Electronics for TPC (GET). The drift chamber has an effective area of around 60x30 cm^2, which matches to the very large acceptance of the S800 spectrometer. This work discusses in detail the results of performance evaluation tests carried out with a low-energy alpha-particles source and with high-energy heavy-ion beams with the detector installed at the S800 focal plane. In this latter case, the detector was irradiated with a 150 MeV/u 78Kr36+ beam as well as a heavy-ion fragmentation cocktail beam produced by the 78Kr36+ beam impinging on a thin beryllium target. Sub-millimeter position resolution is obtained in both dispersive and non-dispersive directions.